1. Field of the Invention
The present invention relates to a process for preparing tetrazole-substituted anthranilic acid diamide derivatives of the formula (I)
by reacting benzoxazinones with amines.
2. Description of Related Art
It has already been described in the literature that tetrazole-substituted anthranilic acid diamide derivatives can be prepared by reacting tetrazole-substituted N-aryl- and N-hetaryl-substituted pyrazole acids with anthranilamides (cf. WO2010/069502). It is also possible to obtain tetrazole-substituted anthranilic acid diamide derivatives by reacting tetrazole-substituted benzoxazinones with amines (WO 2010/069502). The reaction of benzoxazinones with amines proceeds selectively up to a conversion of 90-95%, but at the end of the reaction the tetrazole-substituted anthranilic acid diamide of the formula (I) reacts under basic conditions to form 4-oxo-3,4-dihydroquinazolines of the formula (X). This has a detrimental effect on the purity of the product and the efficiency of the process.
